These sanitary articles typically comprise an absorbent pad which is normally sandwiched between a permeable inner layer of non-woven fabric and an impermeable outer layer of polyethylene.
The manufacture of such articles involves the formation initially of a continuous web incorporating the aforementioned layers, then shaping the web and finally separating the web into single items ready for packaging.
Shaping consists mainly in the cutting of leg contours and, more generally, serves to give the article an outline appropriate for the specified use.
These operations thus necessitate cutting the material and prior art devices used for this type of operation comprise a rotating drum, around which the web is looped partially as it advances in a predetermined direction, and a laser cutting head that operates on the web in the course of its passage over the drum. Laser cutting heads are especially suitable for processes used in the manufacture of sanitary underwear products, by virtue of their low maintenance requirements and their ease of control and adjustment, especially when compared with rotary blade cutter systems adopted in this same technical field, which require frequent replacement of the blades, or at all events, frequent sharpening of the blades.
While the pros of such an application are evident, one disadvantage of using laser cutting is, without doubt, that connected with the cost and overall dimensions of laser generators.
Indeed, although the laser source is designed to bring the entire thickness of the web to sublimation, the presence of mainly fibrous material means that, in many parts of the web, the laser beam passes through the web without coming into contact with the material.
In other words, although the power (and hence the cost and dimensions) of the laser source is such that it is able to cut the web, a large part of the beam is not used.